This job posting is for a Lead Software Engineer position in London paying £45k-£55k. The company leads its sector in innovative e-commerce, CRM, retail, and marketing solutions, and helped with the London 2012 Olympics and Paralympics. The role involves working on transactional websites and a content management system supporting global online activities, developing backend components using techniques like test-driven development and solid principles. Required skills include PHP, XHTML/CSS, JavaScript, XML, SQL, AJAX, jQuery, TDD/BDD, and experience with tools like PHPUnit and Selenium.